There is a lot of confusion about what optometrists really do. We are so stereotypically associated with asking people "Which is better, 1 or 2?" and correcting vision problems that people are sometimes surprised to hear that we do a lot more! To help with the confusion I decided to start this new blog series "My eye doctor can detect which disease?". Some might surprise you, some might not. In today's blog I want to go over one that you might not expect: High blood pressure.

High blood pressure is extremely common. Approximately 20% of adults have high blood pressure with another 20% having high normal blood pressure (which puts them at higher risk of developing high blood pressure later on). Of these people another 20% are unaware that they have high blood pressure at all! This is important because as you may have heard high blood pressure is a silent killer. It has no symptoms so people are often not aware there is a problem until something serious happens like a heart attack or a stroke.

So how can your optometrist help? When we look inside of your eyes during a routine eye exam we aren't just looking for things like cataracts, macular degeneration and glaucoma. We're also looking for signs of systemic (or full body) problems like high blood pressure. The eyes are the only place in the body where we can directly look at your blood vessels without having to cut you open. This means that we can look and see exactly what is happening. In high blood pressure there a few key things that we are looking for.

In this picture you can see the silvering of some blood vessels and also see how some blood vessels are 'nicking' or pinching the ones underneath. This is typically what I see in the average person with uncontrolled, untreated high blood pressure.

Silvering of blood vessels - normally your blood vessels are a nice red colour but when someone has high blood pressure the blood vessel walls thicken. Over time this means that the blood vessels reflect more light and look more silver.

Wavy blood vessels - normal blood vessels in the eye follow a nice smooth path. If blood vessels are really curvy that can be an indication of high blood pressure.

Pressure on the blood vessels - as high blood pressure worsens the blood vessels may actually start to push down on other blood vessels restricting how much blood flows either in or out of your eye.

Bleeds - As those blood vessels crush each other blood can back up and eventually burst the blood vessel causing bleeds in your eye. You can also end up with white areas on your retina that aren't getting enough blood. Imagine it like squeezing a hose: no water comes out one end and water starts backing up on the other side of the blockage.

So much more - we can have things like leaking from blood vessels, swelling of the optic nerve and other signs.

This is high blood pressure gone seriously wrong. Uncontrolled high (very high) blood pressure over long periods of time can lead to a very unhealthy retina.

As you can see, there's no shortage of things that can go wrong in the eye with uncontrolled high blood pressure. Some of the more severe problems (Bleeding, leakage, swollen optic nerve etc) are fairly rare and only occur in very extreme untreated cases of high blood pressure. What I frequently see in my clinic are some of the early signs (the silvering, wavy blood vessels or pressure on blood vessels) and that let's me have a conversation about high blood pressure with you. In some cases your family doctor may already be aware and is either monitoring or already treating the issue. Sometimes though people have no idea and are shocked that they have high blood pressure and that it was found during a routine eye exam! It's important to keep blood pressure controlled to reduce your risk of so many very severe problems and early intervention and treatment is always better than trying to recover from something like a heart attack or stroke.

If you have any concerns that you might have high blood pressure I would urge you to book an appointment with your family doctor. While optometrists can detect high blood pressure it isn't our area of expertise to treat and manage high blood pressure effectively. If we detect it in office we always will send you back to your family doctor to both confirm the diagnosis and if needed start treatment. What's most important is remembering to have regular health checks with both your family doctor and your local doctor of optometry!

If you have any questions about this or anything else feel free to contact us on Twitter, Facebook, Google +, via our website or phone us at (403) 474-6744.